1. Technical Field
The invention relates to an improved tire construction wherein a protective layer extends circumferentially about the tire for deflecting and dislodging lightweight road material before it penetrates the innerliner of the tire. The protective layer is a plurality of circumferentially spaced metal rods located beneath the tread portion
2. Background Information
Numerous tire constructions have been developed which have an internal reinforcement or band of material to prevent sharp objects from penetrating beyond the tread and into the inner air chamber of the tire to reduce puncture and loss of air. Many of these prior art tire constructions use various overlapping steel plates, which although perform satisfactory in preventing puncture, results in an expensive tire which may provide a less than desirable ride characteristic. Some examples are shown in U.S. Pat. Nos. 5,599,987, 560,196, 500,468, 939,611, 1,327,503, 1,431,069, and 3,640,329. Other such tire constructions use a heavy-type of fabric reinforcement such as shown in U.S. Pat. No. 969,722. Another puncture resistant tire is shown in U.S. Pat. No. 1,482,217 which uses a combination of overlapping layers of fabric and wires wherein the wires extend in crosswise fashion with respect to the fashion with respect to the reinforcing strips. The wires extend in a circumferential relationship around the tire and can be staggered and extend crosswise of the fabric reinforcing strips.
U.S. Pat. No. 6,029,725 discloses a tire construction having stiff plates arranged circumferentially about the tire to form a belt which is stiff in the in-plane or steering torsional direction but quite flexible in the radial direction. Although it may provide some puncture resistance, it does not achieve such a result as the present invention wherein circular rods are used to provide deflection of sharp road objects before they penetrate the innerliner instead of providing a physical barrier which prevents penetration.
Therefore, the need exists for an improved pneumatic tire which contains a relatively inexpensive, lightweight protective strip formed a circumferentially spaced cylindrical rod which extends circumferentially around the tire beneath the tread portion thereof, which will deflect many types of sharp objects before they penetrate the body carcass and innerliner of the tire.